LAKE COUNTY – Health officials locally and across the state are warning of an increase in whooping cough, with this year seeing a peak in cases.

An infection that's also known as pertussis, the most severe form of whooping cough typically affects young infants, although all age groups can contract it, the Lake County Health Services Department reported this week.

Lake County Health Officer Dr. Karen Tait said no pertussis cases have been reported in the county, but she's nonetheless urging people to be vaccinated.

Mendocino County health officials also reported no cases of the infection so far in their area.

The California Department of Public Health reported that pertussis case numbers tend to peak every two to three years, with the greatest number occurring between August and September. The last peak was in 2005.

Over the past decade, the disease has led to the deaths of between three and four infants under the age of 3 months in California each year, the state reported. The babies likeliest to die from pertussis are those who have not had any immunizations and whose airways are not fully developed.

So far this year there has been a four-fold increase in pertussis cases as compared to the same time in 2009, Tait said.

Five babies in California have died this year because of pertussis and 900 cases have been reported across the the state, according to a report from Dr. John Talarico, who heads the immunizations branch of the infectious disease center within the State Department of Public Health.

Health officials explained that the germ that causes whooping cough is spread when an infected person coughs or sneezes.

It's highly contagious, and the California Department of Public Health said that studies show that half of the infants with pertussis are infected by their parents, particularly their mothers, which is one reason for encouraging parents and caregivers to be vaccinated.

Infants with the infection will show symptoms beginning with a runny nose and low-grade fever, which later progresses into bursts of cough accompanied by a high-pitched “whoop.” Tait reported that the cough can be so severe that it may lead to vomiting and severe respiratory distress.

Tait said it's not just children who get the infection. All age groups are susceptible, and immunity resulting from childhood vaccination may begin to wear off as early as age 10 years.

In older age groups, the symptoms are less characteristic, but Tait said pertussis should be suspected in anyone who has a recent-onset cough that lasts two weeks or longer. The cough can persist for many weeks, even after the person is no longer contagious, she added.

Pertussis is the most common vaccine-preventable diseases, the state reported.

“Pertussis is a preventable disease that still occurs because too often we don’t address the need for re-vaccination beyond the early childhood years,” said Tait. “In addition, the diagnosis is missed in the older age groups because people don’t think about the possibility of pertussis.”

She said babies are routinely vaccinated at ages 2, 4 and 6 months; between 15 and 18 months; and again between 4 and 6 years of age.

Tait explained that it takes time for the protection to build, so it is important for older children and adults to be vaccinated in order to create a “cocoon” of protection around young infants that they contact.

Because immunizations don't offer permanent protection, Tait recommends that – in addition to the five doses of pertussis vaccine recommended before kindergarten – starting at age 11 children receive Tdap – a vaccine that protects against a combination of pertussis, tetanus and diphtheria. Tdap should be given every 10 years.

Anyone who will have close contact with infants also should have the Tdap booster, Tait said.

When respiratory symptoms occur – such as a new cough in older children and adults that lasts longer than two weeks – Tait urges people to consider the possibility that it might be pertussis. A doctor should be seen quickly if a sick person has come in contact with infants.

She said early diagnosis and treatment can prevent serious illness and can result in measures to control the spread of infection.

Pertussis is treatable with antibiotics when given early in the illness. Under some circumstances, antibiotics are sometimes also given to exposed persons in order to prevent infection. The best prevention, however, is vaccination, Tait said.

Tait said pertussis is an infection that must be reported by health care providers to local public health

authorities.

She said she has been informing local health care providers of the status of pertussis cases in California and current recommendations for prevention, diagnosis and treatment.

To prevent contracting the infection, Tait urges people to keep sick children home from daycare, and to stay away from infants and young children if you're sick.

To get vaccinated, Tait said residents should see their doctor or contact Lake County Public Health at 707-263-1090 or 800-794-9291.

For more information about pertussis, see www.cdph.ca.gov/HealthInfo/discond/Pages/Pertussis.aspx or www.cdc.gov/ncidod/dbmd/diseaseinfo/pertussis_t.htm.

E-mail Elizabeth Larson at This email address is being protected from spambots. You need JavaScript enabled to view it. . Follow Lake County News on Twitter at http://twitter.com/LakeCoNews and on Facebook at http://www.facebook.com/pages/Lake-County-News/143156775604?ref=mf .